Abstract: Fungal viruses （mycoviruses） were widely distributed across diverse fungal species. In recent years， studies on fungal viruses had been significantly increased with the advancement of high-throughput sequencing techniques， particularly regarding their potential applications as biocontrol agents.The current advances in understanding the fundamental characteristics of fungal viruses and the molecular mechanisms underlying virus-host interactions were systematically summarized. Furthermore， key scientific challenges impeding mycovirus research were critically examined， and the potential applications in plant fungal disease management were explored. These comprehensive analyses were aimed at informing the development of innovative biocontrol strategies against phytopathogenic fungi.